The present invention is concerned with suspensions for vehicles that provide two degrees of freedom in the wheels, skis or other points of contact with a surface. More particularly, the present invention is directed to a novel combination of existing suspension designs that can work simultaneously depending upon the loading scenario and desired response from the suspension.
It has been a challenge for suspension designers and engineers to come up with suspension systems that control the camber angle change in an unsprung mass. Whether the unsprung mass is a tire/wheel assembly on a car or skis on a snowmobile, its position with respect to the ground always has dramatic effects on grip and vehicle handling. Existing suspension types such as Macpherson strut, double a-arm (double wishbone), solid-axle, swing axle and trailing arm, to name a few, all only provide good camber control at roll or dive or bump or a combination of two out of the three.
Usually a suspension that has excellent camber control at roll will suffer at bump and dive, while a suspension that has excellent camber control during dive and bump will have less than ideal camber control during roll. Most common suspensions like Macpherson strut and double a-arm suspension can be designed to have acceptable (a relative term) camber angle control at all three cases (bump, dive and roll).
Existing suspension systems provide only one line of motion for the wheel at all times with respect to the vehicle frame/body. At any given time an instant center for the suspension linkage of the wheel can be located on the existing suspension designs. This leads to the known problem of not being able to optimize the dive and roll scenarios simultaneously. There have been some interesting attempts at solving this problem; designs such as Treborn Double Roll Suspension or Orton High Performance Automobile Suspension are some tries that cannot passively provide a stable or working solution to replace the existing commonly used suspension designs mentioned above.
It is therefore an object of the present invention to provide a suspension system that has good bump and dive camber control simultaneously with good roll camber control. Such a suspension system would achieve good results at bump, dive, roll and all combinations of the three. It is a further object of the present invention to provide a suspension system that isolates the response of the suspension system to vertical loads causing bump and dive motion from lateral loads causing roll motion. It is yet a further object of the present invention to provide a suspension system that locks out or isolates a roll suspension from reacting to vertical loads, thus minimizing the undesirable effects of a roll suspension during dive and bump scenarios. It is still a further object of the present invention to provide a suspension system that allows response from both roll and dive suspensions under lateral loads resulting in a coupled camber angle control of the wheel from both suspensions.
The present invention fulfills these needs and provides other related advantages.